Tube socket



Aug. 7, 1962 E. K. RALSTON ETAL 3,048,809

TUBE SOCKET Filed Nov. 10, 1959 INVENTORS Edgar K. Rulsion &

Fig. 2 Harold 0 McGill I ATTO'RNEY United States Patent 3,048,809 TUBE SOCKET Edgar K. Ralston, Wheeler, and Harold C. McGill, Bath, N.Y., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Nov. 10, 1959, Ser. No. 852,000 3 Claims. (Cl. 339-65) This invention relates generally to sockets for the reception and securing of electron tube pin leads for connection in an electrical circuit, and more particularly to such sockets used to perform testing operations on electron tubes.

In the manufacture of electron tubes, it is often the case that a resulting tube has external pin leads which are not aligned parallel to each other and to the tube axis. These bent pin leads may result from mishandling during the various production operations or from faulty fabrication. This problem arises most frequently in regard to miniature receiving tubes which have pin leads of relatively fine wire which is vulnerable to bending. It is obvious that tubes having bent pin leads are not readily marketable because of the difficulty of inserting them in sockets.

It is usually the case in tube manufacturing facilities that a human operator visually determines which tubes have bent leads and picks these tubes out for insertion into a special pin straightening device. This requirement of an additional, separate step in the tube manufacturing process for the straightening of bent pins is a costly one and, furthermore, is not wholh effective because of the possibility that a tube having bent pins will not be picked out for insertion in the pin straightening device.

According to the present invention, a tube socket is provided which has pin straightening means as an in herent part thereof. While this device is very useful as a tube test socket for use in manufacturing operations, it is obviously not limited to that application but may be employed as a tube socket generally.

It is, therefore, the principal object of the present invention to provide an electron tube socket receptive of a tube having bent pin leads so as to cause the straightening of such pin leads upon insertion of the tube into the socket.

It is another object of this invention to provide means for straightening bent lead pins of electron tubes without a separate step in the manufacturing process.

It is another object to provide means for straightening bent lead pins which may be used in a process not requiring visual selection by a human operator.

Another object is to provide a tube test socket having pin straightening means inherent therein.

Another object is to provide a tube socket having a long useful life.

Another object is to provide a tube test socket having pin straightening means therein which may be readily formed by modification of a conventional tube test socket.

These and other objects will become apparent through the following description taken in conjunction with the drawings, in which:

FIG. 1 is a plan view of a tube socket made in accordance with the present invention;

FIG. 2 is a sectional view of one pinhole of the socket of FIGURE 1, taken along the line II-II, as indicated on FIG. 1, partially in elevation;

FIG. 3 is a sectional view of the tube socket of FIG. 1, taken along the line IIIIII therbeof, shown with an electron tube to which said socket is receptive; and

FIG. 4 is a sectional view of the tube socket of FIG. 3 taken along the line IV-IV thereof.

Referring now to FIG. 1, there is shown a circular body of insulating material which is fixedly secured ice to a base of insulating material by screws 12 for the formation of a tube test stand. The insulating member is usually of a thermosetting plastic such as the phenolic type. A socket 15 is located in the center of the insulating member 10 and comprises a generally circular array of small pinholes 17 which may be disposed in a depressed portion 18 of the insulating member 10. The pinholes 17 are of such location and size as to receive the lead pins of an electron r be. The pinholes 17 shown in the embodiment of FIG. 1 are shown in a pattern suitable to receive the leads of a miniature type receiving tube. The pinholes 17 extend through the insulating member 10.

Within each of the pinholes 17, there is located an apertured insert 20 which is fixedly secured within the pinhole and is concentric therewith. The inserts 20 are separated from each other by a portion of the insulating member 10 so that there is no conductive path therebetween.

Referring now to FIGURE 2, there is shown the :apertured insert 20 having a shank portion 21 and a head portion 25. The shank portion 21 and the head portion 25 are parts of a single member, as the insert 20 is shown here, or they are securely fastened together. The shank portion 241 extends into the insulating body 10 and lines the pinhole 17. The outer wall 22 of the shank portion 21 has self locking ridges 23 disposed thereon to securely hold the insert 20 within the pinhole 17. Other means for securing the insert 20 within the pinhole 17 could, of course, be employed. The ridges 23 are a preferred means for securing the inserts 20 because upon forcing the insert into the pinhole the ridges 23 bite into the wall of the pinhole 17 thereby locking the inserts 20 in place. The inner wall 24 of the shank portion 211 is smooth and straight for the easy passage of a tube lead therethrough. The head portion 25 of the insert 20 comprises an abutting surface 26 which rests against the body of insulating material 10 upon insertion of the insert 20 into the pinhole 17. The head portion 25 also comprises an aperture or mouth 27 having one or more beveled portions of which two such portions 28' and 29 are shown.

It is readily seen that the mouth 27 of the insert 20 has a greater diameter than the inner diameter of the shank portion 21.

The beveled portions 28 and 29 slope away from the center of the pinhole '17 so that upon the insertion of a bent pin lead into the pinhole 17 the incoming pinlead will strike one or both of the beveled portions 28 or 29 and be deflected toward the center of the pinhole 17 making it possible that it be inserted into the tube socket and be straightened while the tube is in use or is being tested for electrical characteristics as aforesaid.

The material of which the insert 20 is composed is preferably one which will withstand the frequent contact with incoming pin leads with little wear. For this purpose, many metals are suitable such as hardened steel or tungsten carbide. The insert 20 is secured in the pinholes 17 in a rigid and nonresilient manner so that flexible pin leads will be straightened, that is, the insert 20 is neither springlike nor deformable.

Referring now to FIGS. 3 and 4, there is shown an electron tube socket formed in accordance with the present invention wherein an insulating body 10 has therein a pattern of pinholes 17, each of which has an apertured insert 20 rigidly secured therein. The insulating body 10 is secured to a base 30 which may be of similar insulating material. Contacts in the form of bolts 32 extend through the insulating base 30 in a circular pattern. The insulating base 30 is further provided with an aperture 34. The contacts 32 each provide means for securing a contact clip 36 as is shown in FIG. 4. The contact clips 36 extend radially inwardly from the contact bolts 32 and comprise two resilient prongs 37 and 38. Adjacent pairs of contacts are maintained in an electrically insulated and separated position by means of insulating projections 40 which are disposed on the underside of the insulating member 10. In this manner, the contact clips 36 are positioned so that upon the insertion of an electron tube 50 into the socket, each of the pin leads 55 of the tube 50 will pass through a pinhole 17 and enter between the prongs 37 and 38 of one of the contact clips 36 thereby making good electrical contact through the contact clip tothe contact bolt 32. The contact bolts 32 are ordinarily connected to a circuit used in the testing of the electron tube 50 inserted in the socket. The pin contact clips 36 are of a suitable material such as phosphor bronze or beryllium copper.

A tube test stand formed in accordance with this invention may be readily formed by the modification of a conventional test socket which is used in tube manufacturing operations to test the electrical characteristics of the manufactured tubes and elements therein which are, of course, electrically connected to the pins of the tube. The modification would be effected simply by the insertion of the apertured inserts 20 into the pinholes of the test stand. In this manner, the electrical testing characteristics of the socket and associated circuitry would be in no way adversely affected while the same device would perform the additional function of straightening pin leads which have been bent in previous fabrication. Therefore, operations to be performed on newly made tubes may therefore be reduced by one step which results in important savings. Also, use of a device made in accordance with our invention assures that the pins of every tube will be straightened.

While the present invention has been described in only one embodiment, it will be apparent to those skilled in the art that it is not so limited and that it may take other forms without departing from the scope thereof.

We claim as our invention:

1. An electron tube socket comprising a body of insullating material having pinholes therein located for the reception of the pin leads of an electron tube, a contact member disposed in alignment with each of said pinholes to make conductive contact to pin leads extending through said pinholes and to connect said pin leads into a test circuit, each of said pinholes having an insert comprising an apertured shank portion within said pinhole and an apertured head portion external to and concentric with said pinhole, said shank portion having an outer wall with a plurality of ridges thereon mechanically engaging the wall of said pinhole in a self-locking manner, said head portion having one or more beveled surfaces for the deflection of bent pin leads toward the center of said pinholes to simultaneously straighten the pin leads of a tube upon insertion of the tube into a test circuit.

2. An electron tube test socket comprising a body of insulating material having pinholes for the reception of electron tube pin leads extending therethrough, a contact member disposed in alignment with each of said pinholes to make conductive contact to pin leads extending through said pinholes and to connect said pin leads into a test circuit, each of said pinholes having a metallic insert therein, said metallic insert having an aperture coaxial with said pinhole, said metallic insert having a head portion and a shank portion integrally connected to said head portion, said shank portion disposed within said pinhole and having its outer Wall secured to the wall of said pinhole, said shank portion having an aperture diameter approximately equal to the diameter of one of said pin leads, said head portion having an abutting surface resting against the surface of said body of insulating material and having an apetrure of varying diameter in alignment with said shank portion aperture, said head portion aperture diameter being greatest at the extremity of said head portion remote from said body of insulating material and least in the plane where said head portion joins said shank portion so that upon the insertion of a bent electron tube pin lead into said head portion aperture the wall of said head portion aperture directs said bent pin lead into said shank portion aperture thereby resulting in the straightening of said pin lead simultaneously with the insertion of a tube into a test circuit.

3. An electron tube test socket comprising a body of insulating material having a plurality of pinholes extending therethrough for the reception of electron tube pin leads electrically coupled to the several elements of said electron tube, a plurality of contact clips disposed in alignment with said pinholes so as to make electrical contact with the electron tube pin leads extending therethrough, circuit means electrically coupled to said contact clips so as to place one or more elements of said electron tube in circuit relationship for the testing of the electrical characteristics of said elements, each of said pinholes having a metallic insert therein, said metallic insert having an aperture coaxial with said pinhole, said metalic insert having a head portion and a shank portion integrally connected to said head portion, said shank portion disposed within said pinhole and having its outer wall secured to the wall of said pinhole, said shank portion having an aperture diameter approximately equal to the diameter of one of said pin leads, said head portion having an aperture of varying diameter in alignment with said shank portion aperture, said head portion aperture diameter being greatest at the extremity of said head portion remote from said body of insulating material and least in the plane where said head portion joins said shank portion so that upon the insertion of an electron tube into said socket for the testing of the electrical characteristics thereof any of the pin leads which are bent from the proper axial direction are directed by the wall of said head portion aperture into said shank portion aperture thereby resulting in the straightening of said pin leads simultaneously with the insertion of the electron tube into the test circuit.

References Cited in the file of this patent UNITED STATES PATENTS 1,806,815 Mut-her May 26, 1931 1,890,484 Allenic Dec. 13, 1932 2,481,027 Lawrence Sept. 6, 1949 2,696,535 McLean et al Dec. 7, 1954 2,740,099 Schultz Mar. 27, 1956 FOREIGN PATENTS 562,223 Great Britain J uue 22, 1944 

